Step 39

[matty k]

Hey Tim, I completed the last of my C84's last night and assembled CH01/PS03, and everything checks out ok except step 39. 3 of the 4 pre amps measure a steady 30-40 mV, and the 4th varies, mostly averaging 35. all 4 pass audio at all settings. I know this is under the 50mV value stated in the assembly instructions, just wondering if there's a way to get it lower, or if there's a problem i'm not aware of. thanks.

Matt.

[tpryan]

You'll notice some small drift as the servos correct for offset. It sounds like your modules are working fine.

[infested3d]

Hey Tim,

I've put together a Rev 1.9.1 board. I am measuring 365 mV @ the L3 junction and 413mV @ L4.


Also, for Step 38 I get 12.06V at the R8/R9 junction. From another post I see that's normal, however I'm getting 28.2mV at the R29/R30 junction. Shouldn't I be seeing an amount closer 0VDC?

Is there something wrong or is the card within parameters?

Any help is appreciated.

Thanks in advance.

[infested3d]

For the sake of sharing the info for others who might have similar concerns in the future, what I was told by Tim was:

"What's important is the difference in voltage between L3 and L4. 48mV is fine.

28mV is more than close enough to 0V, you should have no problems."

Much thanks, yet again, Tim.

I hope it's alright that I've shared those words of wisdom.